Butterfly valve



June 7, 1938.

K.. IIDA .BUTTERFLY VALVE Filed April 16, 1936 2 Sheets-Sheet 1 gmc/whom June 7, 1938. K. "DA 2,119,816

BUTTERFLY VALVE Filed April 16, 1936 2 Smets-snee: 2

Patented June 7, 1938 PATENT OFFICE BUTTERFLY VALVE Koji Iida, Itabashi-ku, Tokyo, Japan Application Api-1i 1e, 193s, serial No. 74,758 In Japan May 9, 1935 6 Claims.

ed at the same time a smooth and accurate closing of the closure discs upon their seats has been lacking.

A further object of the invention is to provide means whereby the movement of the closure discs to completely open position is only possible when the closure discs have been moved inwardl furthest from their cooperating seats. 1

A further object of the invention is to provide means whereby the closure discs are urged against their respective seats by equal pressures.

With the above and other objects in view which will become apparent as the description proceeds the invention is described in detail below, claimed in the claims and illustrated in the drawings, in which Figure 1 is a vertical section of the valve according to this invention,

Figure 2 is a cross section taken on the section line A-A in Figure 1,

Figure 3 is a cross sectional view taken at .right angles to the view in Figure 1.

Referring to the drawings in which like reference characters indicate like elements 3' and 4 are the closure discs mounted oppositely on the shaft 5 which is provided with a right hand thread at one end and a left hand thread at the other. The central part 6 of the shaft 6 has a key 1 which slides in a guideway provided in the hub portion 8" of the bevel gear 8. Instead of the key I and the cooperating groove the portion 6 of the shaft 5 may have a polygonal shape and in such case the hub portion of the bevel gear 8 will have a corresponding shape.

The bevel gear 8 is held in position by the bushing I2 which in turn is fixed on the pivotally mounted frame I2 preferably positioned vertically in the valve casing I. on the driving shaft 9 meshes with bevel gear 8.

The driving shaft 9 extends through a cylindrical tube Il which in turn is connected with the frame I2.

The closure discs 3 and 4 are preventedfrom Bevel gear I xed rotative movement with relation to the frame I2 by means of the pin I8 which is screwed into the frame I2 as shown particularly in Figure 1 and cooperates with recessed bosses as shown.

At the upper end of the cylindrical tube II there is provided a clutch member I6 which is provided with two diametrically opposed recesses I4 and I4. The cooperating clutch member I6 slides on the shaft 9 and is provided with two claw members I6 designed to cooperate with the recesses I4 and I 4'. The sliding clutch member I6 is connected to the end `I9 of the operating clutch lever I8 by means of the ring I'I. 0n the lever I8 there is also provided a branch arm 2li. When the lever I8 is operated so as to unclutch the clutch members and moved into the dotted line position shown in Figure l then the branch arm 28 will enter the recess I4 in order to lock the tubular member II and the frame I2 from rotative movement. The locking of the tube II. is only possible when the closure discs I and 4 are brought closest together and furthest from their cooperating seats 2 provided in the casing I.

At the upper end of the driving shaft 9 there is xed a worm gear 2I engaged bythe worm 22 which in turn is fixed to the shaft operated by the hand wheel 24. The clutching elements and worm wheel are enclosed within the casing 23 mounted on the valve casing I. y

In addition to the locking branch 28 provided on the clutch operating lever I8 there is also provided a locking pin 26 which is urged towards the clutch member I5 by the spring 26 seated in the casing 23 normally opposite the recess I4'. 35 When the clutch member I6 is operated so as to remove the claws I6 from the recess I 4 then the pin 26 will enter the recess I4' and cooperate with the branch arm in locking^the tubular member II. 0

In operating the valve the clutch lever I8 is 4 rst .lifted to the position shown in full lines in Figure 1 and in such position the claws I6' of the clutch member I6 enter the recesses I4 and I4' of the clutch member I5 when the closure. discs 8 and 4 are closest together. In this movement of the claws I6 the pin 26 is urged out of the recess'I4' against the action of the spring 26 by the claw member itself.

If the hand wheel 24 is now operated the driving shaft 9, the cylindrical tube I I and the frame I2 will rotate as one bodyand the valve may be moved to fully open position and the valve may be moved from the fully open position to the intermediate closing position as shown in FII- ure 1. When the closure discs have reached the position shown in Figure 1 then the clutch operating lever is moved downwardly to the dotted line position shown in Figure 1 and the claws I6' are removed from the recesses I4 and I4'. At the same time bythe movement of the lever I8 the arm 2li will t into the recess I4 and the pin 28 will t into the recess I4 thereby locking the cylindrical tube il from any further rotation. x Therefore the closure discs 3 and 4 are held 'l firmly in the intermediate position exactly parallel to the valve seats 2. Now if the driving shaft 9 is further rotated by means of the hand wheel 24 the threaded rod 5 will be rotated by means of the bevel gears I0 and 8 and the closure discs are separated from one another gradually -moving towards the valve seats 2. Assuming that the liquid flow is coming from the direction of the arrows in Figure 1 then the closure discs 3 and 4 due to the slidability of the shaft 5 in the hub 8' of the bevel gear 8 will be moved by the pressure of the liquid iiow slightly in the direction of the liquid flow. Such being the case the closure disc 3 located furthest from the liquid pressure ilrst'comes into contact with its valve seat and is first moved into completely closed position. However with the closure disc 3 completely closed the closure disc 4 has not yet come in contact with its valve seat and therelore the pressure is equalized upon both sides of the closure disc 4. Due to this equalization of pressure the closure disc 4 may be easily brought -against its valve seat and pressed ilrmly thereagainst.

From the construction described above it is apparent that the closure discs 3 and 4 are slidable with respect to the driving mechanism therefor and will operate in the reverse manner if the flowshould be in the direction opposite to that of the arrows in Figure l. In such case the closure disc 4 will first close and the pressure will be equalized upon both sides of closure disc 3 prior to the seating oi closure disc 3 upon its seat.

Furthermore since in the closed position the pressure of the liquid flow ,does not act directly upon the operating mechanism of the Valve there is no danger of bending .or breaking the frame and the driving shaft even though there should be a sudden increase of pressure due to any cause. Also in case the closure discs should arrive in an improper position, that is, non-parallel to the valve seat there will nevertheless be no danger of the closure discs spreading apart from one another. Therefore there will be-no danger of damaging the valve seats and the closure discs due to any rubbing action of the closure discs against the valve seat when the closure discs are turned.

It is understood that the above described embodiment is merely illustrative of what is now considered the preferred form.

Having described the details of my invention referring to the accompanying drawings, what I claim as new is:

1. A valve comprising a casing; spaced annular seats on said casing, a frame pivotally mounted in said casing, a shaft slidably and rotatively mounted in said frame having threads of opposite pitch on each end thereof, closure discs having threaded portions threaded on the threaded ends of said shaft, a rotatable tube secured to said fra-me, a second shaft operatively associated with said first mentioned shaft and means for operatively associating said tube with said second shaft to rotate said frame.

2. A yalve comprising a casing, a frame pivotally mounted in said casing and having a tubu- `'liar trunnion, a shaft slidably and rotatively mounted in said frame having oppositely threaded ends, closure discs threaded on said threaded ends, means preventing relative rotation between said frame and saidfdiscs, means extending through said tubular trunnion for rotating said shaft and thereby moving said discs relative to one another and seats on said casing with which said discs cooperate, and means for coupling said tubular trunnion with said shaft rotating means.

3. A valve comprising a casing, a frame pivotally mounted in said casing and having a tubular trunnion, a shaft slidably and rotatively mounted in said frame having oppositely threaded ends, closure discs threaded .on said threaded ends, means preventing relative rotation between said frame and said discs, meansv extending through said tubular trunnion for rotating said shaft and thereby moving said discs relative to one another and seats on said casing with which said discs cooperate, a clutch member fixed to said tubular trunnion and a sliding cooperating clutch member on said shaft rotating means.

4. A valve comprising a casing, a frame pivotally mounted in said casing, seats on said casing, closure discs on said frame cooperating with said seats, means for moving said discs toward and away from said seats, means for rotating said frame together with said closure discs and means for operating said means for rotating said frame only when said closure discs are in completely open position, said last named means including a clutch member having recesses and a sliding cooperating clutch member having claws cooperating with said recesses.

6. A valve comprising a casing, a frame pivotally mounted in said casing, seats on said casi.

ing, closure discs on said frame cooperating with said seats, means for moving said discs toward and away from said seats, means for rotating said frame together with said closure discs and means for operating said means for rotating said frame only when said closure discs are in completely open position, said last named means including a clutch, and means for locking said frame in non-rotative position.

KOJI IRDA. 

